I am accustomed to sleep and in my dreams to imagine the same things that lunatics imagine when awake.
Each problem that I solved became a rule, which served afterwards to solve other problems.
Dubito ergo cogito; cogito ergo sum.
I think; therefore I am.
I hope that posterity will judge me kindly, not only as to the things which I have explained, but also to those which I have intentionally omitted so as to leave to others the pleasure of discovery.